418 WILLIAM NICOLL. 
stomum metcecus, but the last mentioned is of little 
importance, for, as Braun remarked, a short cesophagus may 
be present as also a pre-pharynx. 
The features of primary diagnostic importance are, there- 
fore, the circum-oral collar and papille, the position of the 
genital aperture, the length of the cirrus-pouch, and the 
extent of the uterus with the number and size of the ova; of 
secondary importance are the large testes, the nearly equal 
suckers, and possibly the position of the ovary in Crepid. 
metcecus. That these are of much greater than merely 
specific importance can hardly be denied, and it follows that 
Dist. laureatum Zed., cannot be included in the genus 
Crepidostomum Braun. From the genus Acrodactyla 
Stafford! it differs in having the ventral sucker considerably 
larger than the oral sucker, the rather short cirrus-pouch, 
and apparently the ventral papille not so pronounced. The 
structure of the cirrus-pouch in Acrodactyla is not 
mentioned, but it is presumably muscular. From the genera 
Bunodera Raill. and Patagium Heymann it is  suffi- 
ciently distinguished by the structure of the cirrus-pouch, 
the extent of the uterus, and other features to which I shall 
refer later. In short, it must be regarded as the type of a 
distinct genus, for which I propose the name Stephano- 
phiala, with the following provisional definition : 
Body of medium size, elongated, flattened. Cuticle 
unarmed, Suckers fairly muscular, the ventral sucker being 
larger than the oral sucker, and situated on the border of 
the first and second thirds of the body-length. Oral sucker 
subterminal, with its anterior part swollen and surrounded 
by a row of six equal, muscular, contractile papille, arising 
from the muscle-substance of the sucker, two being ventral 
and four dorsal. Intestine with short pre-pharynx, medium- 
sized pharynx, short cesophagus, and diverticula extending 
to hind end of body. LHxcretory vesicle simple. Genital 
aperture median, midway between suckers. Sinus genitalis 
absent or rudimentary. Cirrus-pouch with muscular walls 
1 * Zool. Anzeiger,’ xxvii, p. 491. 
